Vertical hydrological connectivity (VHC), plays a crucial role in regulating soil water and nutrient cycles, thereby contributing to the sustainability of vegetation restoration. The impacts of anthropic factors, particularly land use changes, on vertical hydrology have gained increasing attention. However, the mechanisms underlying the effects of land use conversion patterns on VHC remain insufficiently understood. To address this knowledge gap, this study investigated the VHC of orchard soils converted from paddy fields (P-O sites) and drylands (D-O sites) using dye-tracer experiments. VHC was quantified using key indicators, including dye coverage (DC), maximum dyed depth (MMD), length index (Li), depth of diffusion area (UniFr), and percentage of preferential pathways (PFfr). It showed that compared with P-O site, D-O sites exhibited significantly higher sand and gravel content, along with greater non-capillary porosity. Additionally, a relatively uniform and vertically distributed root system was observed at D-O sites. Thus, DC at D-O sites was 63.87 % higher than that at P-O sites, indicating stronger hydrological connectivity. Furthermore, UniFr at D-O sites was 12 times higher than that at P-O sites, while PF-fr exhibited the opposite trend, suggesting a more homogeneous infiltration pattern at D-O sites. However, no significant differences were observed in MMD and Li. At P-O sites, dye coverage fluctuated with depth, peaking at 10-20 cm, whereas at D-O sites, a consistent decreasing trend was observed. The stratification ratio (SR) of soil properties were identified as the most critical factor influencing VHC, explaining 70 % of the variation. Specifically, soil porosity (r = -0.60) had a direct impact on VHC, while soil texture (r = 0.80) and root distribution (r = -0.39) primarily influenced VHC indirectly through their effects on soil porosity. These findings suggest that the presence of a hydrological barrier layer in orchards converted from paddy fields restricts hydrological connectivity. To mitigate this limitation, appropriate tillage practices, such as deep plowing, should be implemented to disrupt the impermeable layer and enhance VHC.